British Journal of Industrial Medicine, 1974, 31, 322-328 Br J Ind Med: first published as 10.1136/oem.31.4.322 on 1 October 1974. Downloaded from Notes and miscellanea Pneumoconiosis and byssinosis D. C. F. MUIR Institute of Occupational Medicine, Roxburgh Place, Edinburgh, EH8 9SU On 1 August 1968 the Minister of Social Security loggerheads over the question of pneumoconiosis in referred the following question to the Industrial general and of related disability in particular. Injuries Advisory Council for consideration and The less controversial aspects of the report should advice: perhaps be mentioned first in order to clear the way Whether in the light of experience and current for a review of its more fundamental features. It is knowledge any adjustment should be made in the well written and has concise and clear explanations terms of the definition of pneumoconiosis in of the problems considered. The historical back- section 58 (3) of the National Insurance (In- ground is reviewed in detail, and there is an excellent copyright. dustrial Injuries) Act 1965; and whether any and, description of the work of the Pneumoconiosis if so, what special provision should be made for Medical Panels. There is a great deal of information disablement due to other respiratory conditions in the report which is not available in textbooks of found in the presence of such pneumoconiosis to occupational medicine, and it should be essential be taken into account in assessing the extent of reading for all who have an interest in this field. The disablement due to the disease. summary and conclusions are short and explicit. The Council referred the question to their In- Some of the recommendations represent a dustrial Diseases Sub-Committee for detailed con- tidying-up operation so that the regulations conform http://oem.bmj.com/ sideration. The Sub-Committee met on 29 occasions more closely to modern medical opinion. Such an and their report was submitted to the Secretary of example is given by a suggested new definition of State for Social Services on 27 June 1973. Its publica- pneumoconiosis. The report makes it clear, however, tion was followed by heated controversy in the that the diagnostic practice of the Pneumoconiosis medical and national press. This gradually subsided Medical Panels is regarded m working well and that following an announcement by the Secretary of State a new definition is not intended to imply any varia- in the House of Commons that there would be no tion in current standards. In the case of asbestosis change in the regulations concerning compensation the report suggests a change that appears eminently on September 26, 2021 by guest. Protected for pneumoconiosis. sensible. If inhaled asbestos causes fibrosis of the The report names those organizations and persons lungs, then the patient is considered as having from whom evidence was received. The list includes pneumoconiosis. If those same fibres cause fibrosis many of the recognized experts in the field in this of the pleura alone then he is not. Irrespective of the country, together with representatives of employees, presence or absence of disability associated with management, and other interested groups. How is it pleural plaques, present regulations exclude further possible for such a plethora of informed evidence to consideration because the law is based on fibrosis of be received, for conclusions and recommendations the lungs. The report recommends that this anomaly to be made on this evidence, and for these to be be removed by including the visceral and parietal promptly rejected? If there were general agreement pleura in the term 'lung'. Anatomists are unlikely to among the medical profession as to the 'facts' about quibble too much over this small adjustment. No pneumoconiosis it is probable that the Secretary of change is suggested in the present provisions for dis- State's decision would be regarded as being purely ablement due to other respiratory conditions found political. If there is any agreement among physicians, in the presence of pneumoconiosis or in special however, it must surely be that we appear to be at hardship allowances. The potential of the Pneumo- 322 Notes and miscellanea 323 Br J Ind Med: first published as 10.1136/oem.31.4.322 on 1 October 1974. Downloaded from coniosis Medical Panels as a focus for research is at present. The general requirements for the prescrip- emphasized and the possible disadvantages of isola- tion of an industrial disease would also, at present, tion from the main stream of medical practice and exclude any attempt to enlarge the concept of thought in the National Health Service are noted. pneumoconiosis of coalworkers to include pulmon- The reality of professional isolation of this sort is, ary dysfunction in the absence of pathognomonic of course, present in other branches of occupational radiological abnormalities. Suppose the present medicine and is undoubtedly bad for all concerned, definition 'fibrosis of the lungs due to silica dust, whether within the National Health Service or not. asbestos dust or other dust, and includes the condi- The Council hope that the panels will maintain and tion of the lungs known as dust-reticulation' were develop their contacts with their medical colleagues extended to include fibrosis of the small airways or in the National Health Service. lung which resulted in emphysema. It may be argued The real meat of the report is contained in the that this is exactly the situation in byssinosis, for recommendations that the new definition of pneumo- example. The similarity is misleading, however, since coniosis should continue to exclude bronchitis and byssinosis can be diagnosed by an accurate history, emphysema and that a diagnosis of pneumoconiosis and thereby any ventilatory defect can be definitely should not automatically imply eligibility for benefit. and finally attributed to an industrial cause. No The Committee considered that bronchitis and similar specific and identifiable respiratory disease in emphysema, in the absence of pneumoconiosis as at coalworkers is known at present other than that present defined, was excluded from their enquiry by associated with the radiological changes widely their explicit terms of reference. Where the two co- recognized as being diagnostic of dust disease of the exist the present regulations work well and allow lung. Any functional disorder of the lungs in a coal disability from bronchitis to be taken into account. miner whose chest radiograph did not show typical However, what is to be done about the miner who round opacities could not therefore fulfil the two is severely disabled by emphysema but whose chest general requirements for it to be accepted as occupa- radiograph shows no evidence of small rounded tional in origin. The Committee hold out no hope opacities? Because of the controversy surrounding that it will be possible in the future to distinguish the this subject, details are given of the reasons why such effects of coal mine dust from the effects of cigarette copyright. a man is not eligible for compensation under present smoke and of general air pollution other than by regulations. The problem is traced back to the means of radiology. They consider that a close watch Industrial Injuries Act (1946) which continued the should be kept on research results in case some pro- precedent ofthe Workers' Compensation Act of 1919 gress towards such a distinction could be made. One and of later Acts whereby the State paid special member of the Committee evidently felt like Mr. compensation for respiratory disability if this was Bumble. He issued a minority report suggesting that, a contracted as result of certain defined occupations. if this was the meaning of the original Acts, then it http://oem.bmj.com/ No such special payment was available for other was time for a fundamental review of the rules respiratory disabilities. It is pointed out in the report governing the prescription of diseases for purposes that, for any disease to be prescribed for the purposes of compensation. of this benefit, the Secretary of State must first be The second contentious matter, and the one which satisfied that the disease: generated most heat, concerned the threshold of (a) ought to be treated, having regard to its disease for benefit purposes. The report gives con- causes and incidence and any other relevant con- siderable space to this problem and reviews the siderations, as a risk of occupation and not as a risk development of knowledge concerning the relation- on September 26, 2021 by guest. Protected common to all persons; and ship between pneumoconiosis and disability. The (b) is such that, in the absence of special circum- legal background is relatively straightforward. Since stances, the attribution of particular cases to the 1954 pneumoconiosis has been treated in the same nature of the employment can be established or way as other prescribed diseases and as injuries presumed with reasonable certainty. caused by accident. Under these rules, a disease, Since bronchitis is so widespread in this country once diagnosed, is assessed with regard to the dis- as a result of cigarette smoking and of other pol- ability it causes. A pension or compensation is pay- lutants, it is impossible at present to attribute an able if disability is considered to be 1 % or more. For individual case occurring in an industry such as coal administrative reasons assessments are made only in mining to an occupational cause. This apparently steps of 10% and the minimum pension payable is remains so even if it is known that bronchitis is thus 10%. common in dusty industries. The report points out The effect of the present regulations is that all men that an occupational origin for bronchitis in an in whom a definite diagnosis of pneumoconiosis is individual would be acceptable if the incidence of the made receive a pension since the view is taken that disease in the industry in which he was employed was this must indicate disability of at least 1 %.